What's the optimum virtual background size?

[Damian_AUS]

I've recently been facilitating some branded backgrounds for my business, and have sought images configured to 1920 x 1080 pixels (16:9). My creative agency has supplied them at 3840x2160 (double the size), claiming that it ensures the quality across all screens (TVs, laptops etc). I'm mindful of excessive file sizes bloating our network unnecessarily, but would like to understand how Zoom 'ingests' these and broadcasts them - knowing that there's not unlimited bandwidth (or processing power) to present these, let alone the 'receiving' device to render them. It's my experience that your own VB self-view will look crisper than a colleague's in a meeting. Is there any tech perspective on what's adequate/ideal vs what's simply excessive/redundant?